title: Tumorigenicity of 3'-hydroxymethyl, 3'-formyl, and 3'-carboxy derivatives of 4-(dimethylamino)azobenzene in rat liver.
abstract: Male Sprague-Dawley rats were fed a cube diet containing 2.51 mmol/kg of 3'-methyl-4-(dimethylamino)azobenzene (3'-Me-DAB), 3'-CH2OH-DAB, 3'-CHO-DAB, or 3'-COOH-DAB (at a level equivalent to 0.06% 3'-Me-DAB in the diet) for a period of 1 to 3 months. Almost all the livers of rats given 3'-CH2OH-DAB for a period of 2 to 3 months or 3'-Me-DAB for 3 months showed marked cirrhosis macroscopically. The common histological findings were cholangiofibrosis with or without markedly atypical bile ducts. Moreover, one hepatocellular carcinoma was found in the liver of a rat given 3'-Me-DAB and one in the liver of a rat given 3'-CH2OH-DAB for 3 months. On the other hand, 3'CHO-DAB and 3'-COOH-DAB did not induce these changes (including neoplastic nodules) at all. Consequently, 3'-CH2OH-DAB, like 3'-Me-DAB, was found to be a hepatocarcinogen.
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002273:Carcinogens; D004032:Diet; D008099:Liver / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D008749:Methyldimethylaminoazobenzene; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D004124:p-Dimethylaminoazobenzene / Q000031:analogs & derivatives*
chemical_list: D002273:Carcinogens; D008749:Methyldimethylaminoazobenzene; D004124:p-Dimethylaminoazobenzene